1963 Impala Powerglide to 700R4 swap

I have a 1963 Impala with a mild small block 350. I'm swapping the Powerglide out for a 700R4 (out of a 1990 Formula Firebird). I know it will come with a 30-spline tailshaft which will have to be changed to a 27-spline. Is this possible or is there an easier/less expensive way to alleviate this issue. Also does anyone know which crossmember I should use? Which kits will I need to make this transmission work with the car? Since the driveshaft is a 2 piece does that mean I only need to get the driveshaft closest to the transmission shortened? Any and all advice on how to make this proccess as painless and the least expensive would be appreciated.

Go to your local parts store and buy a yoke for the trans you have, if needed they have u joints to match different size ends. thats way cheaper than swapping an output shaft. you can have the driveshaft shortened by a good drivetrain shop i use drive train specialists (in OKC) last one i had them shorten cost $50.im also looking for a crossmember to do the same. you would think some one would manufacture one by now..... for now i removed the 6cyl/3spd xmember and cut the ends off of it to move them back 2 inches (approximate) but i noticed the trans mount holes are not symetrical across the width of the xmember so im left scratching my head. if the 6cyl is off center is the v8 center?? i guess im going to weld up a custom one so i can drive it unless someone knows of a 700r4 crossmember for 58-64 chevy cars (impala). later

You also need a 700R4 stand alone harness. they are available from summit racing for less than $50. the harness w module has an adjustment to set the lockup of the torque converter. without the stand alone harness the 700R4 will not operate correctly. that should be all you need.(and i need) later, Dan

I actually found 2 other sites that sell an x member for our cars one for $95 and one for $99. im ordering the $99 tomorrow instead of the $175 part. if you ever bother to check back on this ill send you the website and let you know how mine fits. later, Dan

You dont have to modify the sheet metal on the car. It will fit just fine. You will have to modify the crossmember for the transmission since the 700r4 sits a few inches farther than the powerglide. I sell a direct bolt on crossmember that eliminates the need to cut and modify your original crossmember. I sell them on Ebay for $145. If you need it let me know. My ebay name is TunasGarage2009. You can also email me at Tunasgarage@yahoo.com. Also if you mention you saw this on Car Craft I'll knock off $20. Thanks from Tuna's Garage!!

I know it's been a while but here is where I'm at. Decided against the 700R4 went with the 2004R. Identical length to the powerglide, bolts right up, and is 27 spline. No need to modify the driveshaft. Other difficult part was the crossmember. Plenty of 700R4 crossmembers for a '63 Impala but that won't work. What should work is a TH400 crossmember from www.dr409.com That's a work in progress but I'll update that as soon as I find out hopefully it won't take 3 years this time

I got a 64 impala with a 283 and put the 200r4 with it. I made my own cross member, it looks rough but works. I drill the factory holes a little bigger to fit 7/16 grade 5 bolts in. http://www.cardomain.com/ride/2676294/1964-chevrolet-impala/page-4The 700r crossmember will not work, the mount is off, 4 inches I think. Its not running but its held for a few months so far. My powerglide is a 16 spine, and the 200r4 is a bit longer so I got to shortin the driveshaft.